球墨铸铁管的防腐直接关系到管道的长期的使用性和安全性，因此是衡量管网技术及运行状况的一个重要指标。因铸铁中存在石墨，球墨铸铁中的石墨以球状形式存在，并不影响基体材料的力学和机械性能，但据10个典型城市调查结果显示，我国城镇供水管网静漏失率达到12~13%，远远超过了国家要求城市漏失率控制在6%以下的标准，所以管道防腐一直是我们当前一个热门的课题。
　　1984年，英国水研究中心做出的结论认为：球墨铸铁管的锌层外防腐是非常重要的，可以有效地减少腐蚀。圣戈班穆松桥认为，为了加强管道的外防腐能力，有必要将锌层的密度提高到200g/m2。
　　对球墨铸铁管来说，到目前为止，锌加沥青的外防腐应是最好的也是最基本的防护材料。对于腐蚀性较强的地区的管道铺设，可以在基本防护层的基础上，外加聚乙烯膜套，或聚亚安酯涂层，或聚乙烯涂层等形式，来进行特殊保护。


　　Ductile cast iron pipe corrosion is directly related to the pipeline long-term use and safety, so it is an important index to measure the network technology and running state. Graphite in cast iron, graphite in nodular cast iron in the form of graphite, does not affect the mechanical and mechanical properties of the matrix material, but according to 10 typical urban survey results show that the static leakage rate of urban water supply pipe network reached 12~13%, far exceeding the national requirements for urban leakage rate control in 6% below the standard, so the pipeline corrosion has been a hot topic in our current.
　　1984, UK water research center to make the conclusion that outer layer of nodular cast iron pipe zinc corrosion is very important, can effectively reduce the corrosion. Saint Gobain Mu Songqiao believes that, in order to strengthen the anticorrosion ability of pipeline, it is necessary to improve the zinc layer density to 200g/m2.
　　The ductile iron pipe, so far, anticorrosive zinc plus asphalt is the best and most basic protection material. For the corrosive areas of the pipeline laying, can be in the basic protective layer on the basis of external polyethylene film, or poly Yaan ester coating, or polyethylene coating, etc., to carry out special protection.